如何在 SAS 企业指南中仅使用 PROC SQL select char 变量？

Question

I have the following code:

PROC SQL INOBS=10 OUTOBS=10;
   CREATE TABLE WORK.FREQUENCY_&ColumnName AS 
   SELECT t1.&ColumnName, 
            (COUNT(t1.&ColumnName)) AS COUNT_of_&ColumnName
      FROM &libname..&tblname t1
      GROUP BY t1.&ColumnName
      ORDER BY COUNT_of_&ColumnName DESC;

This code is working but with this code I am selecting all types of variables, however I would like to select only if a variable is CHAR.

Is there a way that I create this condition with a simple where clausule? Or do I need to create a 'if condition'? If yes, how can I create it?

Thank You!

Answer 1

I don't have a SAS installation available right now but this code should work

data _null_;
  /*
  The relevant columns are probably named differently;
  Check the table sashelp.vcolumn what the values in COLTYPE for character variables actually are
  Don't know exactly out of my head
  */
  set sashelp.vcolumn(where=(MEMNAME eq 'MY_TABLE' and COLTYPE in ('CHAR', 'VARCHAR'))) end=eof; 
  
  attrib COLNAMES format=$1000.;
  retain COLNAMES;
  
  /*
    the following two lines concatenate all extracted column names;
    choose one of the two
  */
  /*concatenate all variable names in a string using || operator*/
  COLNAMES = compbl(COLNAMES) || ', ' || compbl(COLNAME);
  /*or via function catx*/
  colnames=catx(', ',colnames,colname);

  /*define a macro variable to hold all determined columns*/
  if eof then do;
    call symput('M_COLNAMES', compbl(COLNAMES));
  end;
run;

/*print all found columns*/
%put Character columns: &M_COLNAMES.;

You can then use the macro variable M_COLNAMES in your select statement. This should give you an idea how you can do this.

Don't hesitate to ask further questions.